Brake cylinder hone



Feb. 10, 1953 T. E. BROOKS BRAKE CYLINDER HOME 2 SHEETS-SHEET 2 FiledNov. 50, 1948 4 ThomasE.

Patented Feb. 10, 1953 UNITED STATES TENT OFFICE BRAKE CYLINDER HONEThomas E. Brooks, Clarinda, Iowa, assignor to Lisle Corporation,Clarinda, Iowa, a corporation of Iowa 16 Claims.

This invention relates to cylinder hones, and includes a device of thatgeneral nature having a hone body and abrasive members that areexpandible and contractible and adapted to engage the surface of thecylinder wall.

A serious objection to previous cylinder ho es had to do with long andshort cylinders. A single cylinder hone was not effective for grindingboth long and short cylinders.

If a long hone was used on a short cylinder, the inner ends of theabrasive members became more worn than the portions extending out of thecylinder. Moreover, the hone tended to form a bell mouth on thecylinder; there was no resistance to the expansion of the outer ends ofthe abrasive members, and as a consequence they were expanded more thanthe inner ends, forming a taper of the abrasive members which caused thebell mouth of the cylinder.

On the other hand, if a short cylinder hone was used on a long cylinder,the whole surface of the cylinder was not evenly ground, leaving ridges.

An object therefore of the present invention is the elimination of theabove objection, and the provision of a cylinder hone which is speciallyadapted to ready interchangeability of long and short abrasive members.

A more specific object is the provision of a novel construction having acentral shaft, a pair of chucks or end members on the shaft, one endmember being axially movable with respect to the other, and abrasivemembers supported solely by the end members.

Another objection to revious types of cylinder hones had to do withblind end cylinders. Ordinary cylinder hones are not effective forgrinding the inner end of a blind end cylinder. This is caused by thefact that the abrasive members do not extend fully to the inner end ofthe hone body, due to improper construction of the bone body.Furthermore, on adjusting the hone for expanding the abrasive members,portions of the hone body extend beyond the inner end of the abrasivemembers in cases where they would not extend beyond the abrasive membersin all positions of adjustment. The present objection applies also inthe case of a stepped cylinder having portions of different diameterswith a shoulder at the juncture thereof.

Another object therefore of the present invention is the elimination ofthe above objection, and the .provision of a cylinder hone which isspecially adapted to grinding blind end cylinders.

A- more specific object is the provision of a cylinder hone having anovel construction in which the entering ends of the abrasive membersextend into close proximity to the respective end of the hone body.

Still another object of the invention is the pro vision of a cylinderhone in which the entering ends of the abrasive members extend intoclose proximity to the respective end of the hone body in all positionsof adjustment of the hone.

With these and other objects in view, my invention consists in theconstruction, arrangement and combination of the various parts of mydevice whereby the objects contemplated are attained as hereinafter morefully set forth, pointed out in the claims and illustrated in theaccomanying drawings in which:

Figure 1 is an elevational view of the cylinder hone in expandedposition;

Figure 2 is similar to Figure 1, showing the hone in retracted position;

Figure 3 is an enlarged longitudinal sectional view of the hone taken online 3-3 of Figure 5;

Figure 4 is a view similar to Figure 3, showing the hone with shortabrasive members therein;

Figure 5 is an end view of the device taken from the top of Figure 3;

Figure 6 is a sectional view taken on line 6-6 of Figure 1;

Figure 7 is a sectional view taken on line s i of Figure 1;

Figure 8 is a view similar to Figure 7, but showing the cylinder hone ina cylinder with the abrasive members biased toward expanded posi tionand engaging the cylinder wall;

Figure 9 is a detail view of one of the abrasive members and taken online 9-9 of Figure 3;

Figure 10 illustrates the cylinder hone in a short blind end cylinder;

Figure 11 illustrates the hone in the large bore of a stepped cylinder;and

Figure 12 is a view showing a portion oi a modified form, oriented inaccordance with the upper left-hand corner of Figure 4.

Referring now in detail to the drawings, the device, as illustrated inFigure 1, includes the hone proper l2 and an adapter I l secured theretoand provided for connecting the hone with a driving tool. The adapter Mmay be conventional and preferably includes a flexible portion it as isusual in such types of adapters.

The hone proper I2 includes a central shaft :3, which for convenienceherein, may also be referred to as a body member because of its functionof supporting all of the elements of the hone. The shaft [8 extendsbeyond the hone atone end 3 where it is provided with threads asindicated at 20. The adapter [4 is secured to this threaded portion bymeans of a set screw 22 or other convenient means. The shaft Or bodymember 18 is polygonal in cross section and, as herein illustrated, ishexagonal.

Mounted on the shaft or body member it are a pair of chucks or endmembers 24 and 26. The end members 24 and 26 are similar to each otherin construction. Referring first to the end member 24, this memberincludes a main body portion 28 in the form of a short axis cylinder andis provided with a central hole 30 for receiving the shaft 18. The hole30 is of the-same cross sectional contour of the shaft so that 'the'endmember rotates with the shaft.

An axially extending flange 32' is formed at the periphery of the bodymember 29 and extends toward the other end member 25. The 'fiange't's ispreferably formed integral with the body member -28"and' isformed'by'-=cii tting away a'cen'tral cavity.

A plurality of slots 34 are cut-'in-the hod'y member 28 and flange 32.The slotsh's i aiepreferably three iii-number and'extehd radially of theend-member and terminate -inwardlyin surfaces 36'. The slots 34 arecut'e'ritirely'thron'gh the body member"28"and"open axially through bothends of the end-member; t'h'e slotsthu's opening radially outwardly andaxially of the end member.

A plate 38 is 'iitt'edionthe' end member 24 on the side oppositetheilan'ge 32. The plate 33 is provided with aperi heral bead 4%! overwhich is turned a flange 4 2 formed on thebody member 28. The flange"qlz'tliu's clamps the plate 38 securely on the endmeriiberand the platecloses one endoi the slots 34. The plate 38 is provided with a centraltapered-holster receiving a reduced portion 44 of 'the shaft l8. Theportion 44 is then swaged or peened'to secure the plate 38 imposition.Theendiii-ember24 is thusfixed on theshaft orb'ody memberi8,'bothagainst'axial movement and against'rotation.

The end memberfi'fii's'siniilar in most respects to the end member'24,including thebody'p'ortion 46, flange 48 and sldtsiiil',- the latterhaving radially inner surfaces 52. -An end plate '51?) is secured inplace similarly to the plate 38. The bbdymember 46 is provided \vith a"centralhole 56 for receiving the shaft (8 and is of course of the samecross sectional contour. The plate 54 is provided with arena-a1cpenmgbutn this case the plate is not'fix'edlysecured to the shaft. Thus the endmember ZGJis 'fix'edi'aga'inst rotation on the" shaft; but isfree'tomove axially thereon.

A 'c'or'npression "spring "58 surrounds the threaded portion'ifl oftheshaft and is received ina hollow portion to of aimt G2- tlireaded-:nthe threaded portion "20.

The notches 34 and it' will be seen'irorn the above, are spacedbircdinferentially around the end members. The notches'are-"also in"axial alignment rorthere ceptio'no'f abrasive members indicatedgenerally at 64. Each abrasive member :54 includes an elongated channelmember 63 whichfm'ay be rectangular in cross section having a; bottomwall '68 (Figureso to 8) and side wallslllq Secured in the channel '66is an abra- 'sive stone 12. The stone maybe rigidly secured in place byclamping the sidewall 19 thereon.

Substantiallycentrally' of the abrasive member '64 are a pair oflugs 1'4which may be struck out from the bottom wall68 a indicated in Figure 6.These lugs extend perpendicular to the bottom wall 63 and then inwardlytoward each other.

A leaf spring is secured to the channel meniber by means of the lugs it.The leaf spring 16 preferably is provided with notches cut in from itslateral edges to receive the lugs M to prevent longitudinal displacementof the spring or channel. The lugs 14 are then clamped in place over theleaf spring. The channel 66 and spring it are thus connected to eachother at a point substantially centrally of each. The ends E8 of theleaf spring 75 are normally biased away from the channel or abrasivemember.

Additional lugs 83 are struck out of the channel member K56. These lugs85 are arranged in pairs and are disposed adjacent the ends of theabrasive member. The lugs 81! are struck out from the side walls F0andbent down so as to be positioned substantially in the plane of thebottom wall 58 and form lateral projections on the channel 56.

The abrasive members as are inserted in the aligned slots 3:! and 55 asbest illustrated in Figure 3. The end member 25 is axially adjustable onthe shaft or body member 13 by means of-the nut 62. The end member SS isretracted away from the end member 24' so that thefiang'esxiii and 4eare spaced at least as far "apart as the opposite outside edges of thelugs 83. The'abrasive members 64 are then inserted into the alignedslots so that the ends ES-of the leaf 'springs rest on the surfaces 35and 5201 the slots. The abrasive members can then be gripped in onehandand compressed radially" inwardly and then the end member 25 is adjustedtoward theothere'nd member by turning the nut 62. Theend member 25 isrun up toward the'other and member to the position whereinthefl'angest'i and 48 overlie the lugs 89. The abrasive members 6:; arethen prevented from falling out of the slots" or being withdrawntherefrom.

In operation the end member 26 can be retracted from the oppositeend'member to a position similar'to that shown'in Figure 2 wherein theabrasive members either'retract radially inwardly by themselves or canbe retracted by applying pressure by the hand. The hone can then beinserted'eas'ilyiritoa cylinder and'after the insertion of the hone'theend member 28' is adjusted t'oward the other end member. The ends 18of the leaf springs are'then engaged' by the plates 33 and Btwhiclibows-the leaf springs and biases them radially outwardly, forcingtheabrasive members radially outwardly intoengagernent with the surface'ofthe. cylinder wall.

The upper endof the hon 'as seen'in Figures 1 to 4 will be referred toas 'the' entering end. that is, the end which enters the cylinder. Thethickness ofthe plate "38 is minor and as a consequence the ends of theabrasive members are in close p'roxi'n'iityto the upper surfaceof'thehone. In the'case-ofblind end cylinders such as illustrated in Figure 10the abrasive members engage the surface of the cylinder wall to a pointclosely'adjacentthe closed or-blihd endof the cylinder.

One of the principal advantages of the present invention resides-in thatfeature wherein different length abrasive-members can be inserted atwill. In grindihgblind end cylinders, or the large diameter ofs't'e'pped cylinders, it is desirable that th abrasive members be no-l-on-gerthan the length of the cylinder being operated on." lif -theabrasive members are longer than thecylinder thecylinder may be groundproperly, 'but the outer ends of the abrasive members whichextend out ofthe cylinder are not worn down; leaving a ridge between'theouter-and-ihne'r portions. The

abrasive members must then be dressed so that they are uniform on theirabrading surfaces. All previously known cylinder hones are objectionablein that they are not readily adapted to quick change of difierentlengths of abrasive members, and hence not as effectively adapted foruse with different length cylinders.

In the case of the present invention, various lengths of abrasivemembers are provided to correspond to the different lengths ofcylinders. The abrasive members illustrated in Figure 3 are adapted foremcient operation in the case of a cylinder of the same length, then ifa shorter cylinder is to be ground the abrasive members can be removedquickly merely by turning the nut 62 and retracting the end member 26.Then shorter abrasive members, such as illustrated in Figure 4, can beinserted and securedin place as described above. A shorter cylinder canthen be honed with the same eificiency and effectiveness as in the caseof the abrasive members shown in Figure 3 employed in a longer cylinder.

The abrasive members 68 are given considerable radial movement comparedwith the axial movement of the end member 26. The axial thrust of theend member 26 is exerted on the ends 18 of the leaf springs and due tothe bowing of the leaf spring the abrasive members are thrust radiallyoutwardly a considerable amount relative to the axial movement of theend member 25. This is in contrast with previously known types anddevices such as those employing Wedges, etc.

Another important advantage of the invention resides in the fact thatthe brasive members are supported entirely by the end members 24 and 2%.A simple construction is thus effected. Complicated arrangements ofmechanical elements heretofore employed are thus eliminated. The deviceis strong and rugged. In the rotation of the device, the abrasivemembers are engaged and supported by the sides of the slots 3% and 59.The rotational thrust is thus not taken up by the leaf springs, thelatter being employed solely for biasing the abrasive members radiallyoutwardly.

I wish to call attention to the fact that the ease of interchangeabilityof the abrasive members is made possible by the simple construction ofthe hone. Entire abrasive member can be removed bodily and replaced byothers by a simple adjustment of the hone. This is in contrast withother types of hones wherein a fixed arrangement is provided andabrasive carriers, such as the channels 66 must be of fixed length. Inthe present case the length of the hone is determined by the spacing ofthe end members and the abrasive members are of the same length as suchspacing and are carried by the end members. There is no additionalconstruction required for supporting the abrasive members.

Figure 11 shows a stepped cylinder 84 having a small diameter portion 86and a large diameter portion 88 with a shoulder 90 therebetween. Ineffect and for purposes of grinding, the large portion 88 is a blind endcylinder. The hone as illustrated in Figure 11 engages the shoulder 90and it is desired to grind the surface of the large portion 88 to apoint as close as possible to the shoulder 99. The device of the presentinvention accomplishes this purpose effectively.

Figure 12 illustrates a modified form in which the plate 38 is providedwith slots 92 in register with the slots 34, which extend radiallyinwardly a portion of the depth of the slots 3 With this arrangement theends of the abrasive members can extend through the slots 92 in the endplate while the radially inner portion of the slots 34 are covered toprovide thrust surfaces 94 for the ends of the leaf spring. In this Waythe ends of the abrasive members at the entering end of the hone can bemade to extend fully and entirely to the end of the whole device.However, in the construction previously described it has been found thatfor all practical purposes the ends of the abrasive members terminatesufficiently close to the entering end of the hone.

While I have herein shown and described certain preferred embodiments ofmy invention, manifestly they are susceptible of modification andrearrangement of the parts without department from th spirit and scopethereof. I do not therefore wish to be understood as limiting myinvention to the precise forms herein disclosed, except as I may be solimited by the appended claims. l

I claim:

1. A grinding tool, comprising, in combination, a body member, a pair ofaxially spaced end members mounted on said body member, each end memberhaving a radially extending body portion and an axially extendingperipheral flange, the flanges on said end members being directed towardeach other, said end members having axially aligned, circumferentiallyspaced slots therein, said slots being cut through said flanges andextending radially into said body portions, and abrasive members mountedin respectively aligned slots, each abrasive member including a stoneand being mounted on a leaf spring, the ends of the leaf spring engagingthe radially inner ends of the slots, the leaf spring thereby biasingthe stone radially outwardly, said abrasive members having lateralprojections adjacent their radially inner portions in position forengaging the portions of said flanges defining the slots therein forlimiting the radially outward movement of said abrasive members.

2. A grinding tool comprising a stem, a pair of axially spaced endmembers mounted on said stem, flanges on each end member extendingtoward the other end member, each end member having a plurality ofcircumferentially spaced slots extending radially therein, the slots ofsaid pair of end members being aligned, abrasive members positioned inpairs of aligned slots, each abrasive member being in engagement with aleaf spring, the ends of said leaf spring engaging the inner radial endsof the slots, thereby biasing the abrasive member radially outwardly,and lateral projections adjacent the radial inner portion of theabrasive members, said lateral projections being located between saidend members and adapted to engage the radial inner surface of saidflanges, whereby the radial outward movement of said abrasive members islimited.

3. A grinding tool comprising a stem, a pair of axially spaced endmembers mounted on said stem, flanges on each end member extendingtoward the other end member, each end member having a plurality ofcircumferentially spaced slots extending radially therein, the slots ofsaid pair of end members being aligned, abrasive members positioned withtheir respective ends in aligned slots, resilient bowed leaf springsengaging said abrasive members and biasing said abrasive membersradially outward from said slots, lateral projections-intermediate theends of said abrasive members and adiacentthe radial inner portionof'the abrasive members, said lateral' projections'being located betweensaid end members and adapted to engagethe-radial inner surface of saidflanges, whereby the radial out-c ward movement of said abrasivemembers. is limited," and means on said stemoperatively associated withat least one of said end members for 'varying'the spacing between said'end members.

4. A grinding tool comprising a stem, 2. pair of axially spacedendmembers-mounted on said stem, one of said end members being slida-bleon said stem, flanges on each end member-extending toward the other endmember, each end member having a plurality ofcircumferentially spacedslots extending radiallytherein; the slots of said pair of endmembersbeing aligned, abrasive member's positioned with-their respective endsin aligned slots, eachabrasive member beingin engagement with a leafspring, the ends of'said leaf spring engaging the inner radial ends ofthe slots, thereby biasing the abrasive member iradially outwardly,lateral projections adjacent the radial inner portion of: theabrasivemembers, said lateral projections being located between said-endmembers and adapted to engage the radial inner surface of said flanges,whereby the radial outward movement of said abrasive memhers is limited;andmeansfor varying the spacing between said end members, said lastmeans including the leaf: spring for'biasing the end members-apart, anut-threaded to said stem, and a springpositioned-between said nut andsaid slidable endmember.

A grinding tool comprising a-stern, av pair of axially spaced endmembers-on sai-dstem, flanges on each endimember'extending toward theother end member,'eachend' member having alplurality ofvcircumferentially spaced-slots: extending radially therein, the slotsof. said pair of end membersbeing: aligned, abrasive members positinnedwith their respectiveends in aligned slots, each abrasive member beingin engagement with a leaf spring, the ends of 'said leaf spring engagingthe innerradial ends of 'the slots, thereby biasing: the abrasive memberradially outwardly, lateralfprojections'adjacent the radial innerportion of the abrasive "members, saidlateral'projections being loeatedbetween said end members and adapted to engage vthe'radia'lrinnersurface of'said-fianges, whereby the radial outward movement ofsaidabrasive members is limited, outer end plates extendingaorosstheouter open ends ofthe slots andzadapted to engage the axialends ofth'e springs, and meanson said-stem operatively associated with Vat least one of said end members for varying the. spacing between saidend' members, whereby the force with which the abrasive members aretbrustra-dially outwardly is varied;

6. A grinding toolcomprising astem, a pair of axiallyspaced and memberson: said stem, flanges on each end-member extendingtoward the other 'endmember, each end :member having a plurality of circumferentiallyspacedslotsextending radially thereimthe slots of said pair of endmembers being aligned; abrasive members positioned with theirrespeotiveends in aligned slots, each abrasive memberbeing in engagement with aleaf spring, the ends of said leaf spring engaging the inner radialends-ofthe slots, thereby biasing the --abrasive member radiallyoutwardly, lateral projections adjacent the radial inner portion of theabrasive membersrsald lat-v era l projections being located between-saidend members and adapted to engage the radial-inner surface of saidflanges, whereby the radial outward movement of said abrasive members islimited,"outer end plates extending across-the outer open axial ends ofthe slots and adapted to engage the ends of the springs,- means on saidstem operativelyassociated with at least one of said end' members forvarying the spacing between said end members, whereby the'force withwhich the. abrasiv members are thrust radially outwardly is varied, andthe projected lengthlof said springs being longer than therespectiveabrasive members, the ends of said springs engaging said outer endp1ates,and the endsoi said abrasivev members being spaced from saidouter end plates, whereby there is no binding therebetween.

7; A grinding tool comprising astem, apair of axially spaced end memberson saidv stem, flanges on each end-member extending toward the other endmember, each and member having a plurality of circumferentiallyspacedslots extending radially therein, the slots; of-saidpair of" end membersbeing aligned, abrasive members positioned with their respective-ends inaligned slots, each abrasive member being mounted on a leaf spring; theends of saidleai spring engaging the inner radial ends of the slots,thereby biasing the abrasive; member radially outwardly, lateralprojections adjacent-the radial inner portion of theabrasive.membersusai'dlateral' projections being locatedv between: saidend members and adapted to engage the radial-inner surface of saidflanges, whereby the. radial outward movement of said abrasive membersis limited, and outer end lips extending across the outer open axialends of the slots adjacentrthe radially inner ends or" said slots;saidouter end lips adapted to engage-the axial endsofithe springs, saidlips being small enough to leave the greater portion of the slotsunobstructed.

8; A grinding tool comprising a stem, a pair of axially spaced endmembers cnsai-dcstem, flanges on eachencl member extending toward theother end membeneach end member having aplurality of circumferentiallyspaced slots extending radially therein, the slots of saidpa-ir of endmembers being aligned, abrasive members: positioned with theirrespective ends in alignedslots, eachabrasive member being mounted on aleaf spring, the ends of said leaftspring engaging the inner radial endsor the slots, .therebyibiasing the abrasive member radia ly outwardly,lateral projections adjacent the radial'inner portion of the abrasivemembers, said lateral-;projections. bein located between said endmembers and adapted to engage the radial inner surface of said flanges,whereby the radial outward movement of said .abrasive'members islimited, outer end lips extending-across the outer open axial ends ofthe slots adjacent the radially inner ends of: said slots, said outerend lips adapted to. engage the axial ends of the springs, said lipsbeing small enough to leave the greater portion of the-slotsunobstructed, and said abrasive members extending axially outwardly ofsaid outer end lips.

9. A grinding-tool comprising a'stem, ,arpair of axially spaced endmembers on said stem, the first of said pair of end members being fixed;on one end-0f said stem, flanges oneach endmember extending toward theother endmember, each end member having a plurality of circumferentiallyspaced slots extending radially therein, the slots of said pair of endmembersbeingaligned,

abrasive members positioned with their respective ends in aligned slots,each abrasive memher being mounted on a leaf spring, the ends of saidleaf spring engaging the inner radial ends of the slots, thereby biasingthe abrasive member radially outwardly, lateral projections adjacent theradial inner portion or" the abrasive members, said lateral projectionsbeing located between said end members and adapted to engage the radialinner surface of said flanges, whereby the radial outward movement ofsaid abrasive members is limited, outer end lips extending across theouter open axial ends of the slots adjacent the radially inner ends ofsaid slots, said outer end lips adapted to engage the axial ends of thesprings, the outer end lips on said first end member being small enoughto eave the greater portion of the slots unobstructed, and said abrasivemembers extending axially outwardly of said outer end lips on said firstend member.

10. A grinding tool comprising a stem, a pair oi axially spaced endmembers on said stem, each end member having a plurality ofcircumferentially spaced slots extending radially therein, the slots ofsaid pair of end members being aligned, abrasive members positioned withtheir respective ends in aligned slots, each abrasive member being inengagement with a leaf spring, the ends of said leaf springs engagingthe inner radial ends of the slots, outer end plates extending acrossthe outer open ends or" the slots and adapted to engage the ends of thesprings, means on said stem operatively associated with at least one ofsaid end members for varying the spacing between said end members,whereby the force with which the abrasive members are thrust radiallyoutwardly is also varied, the projected length of said springs beinglonger than the respective abrasive members, the ends of said springsengaging said outer end plates, and the ends of said abrasive membersbeing spaced from said outer end plates, whereby there is no bindingtherebetween.

11. A grinding tool comprising a stem, a pair of axially spaced endmembers on said stem, the first of said pair of end members being fixedon one end of said stem, each end member having a plurality ofcircumferentially spaced slots extending radially therein, the slots ofsaid pair of end mem- I bers being aligned, abrasive members positionedin pairs of aligned slots, each abrasive member being mounted on a leafspring, the ends of said leaf springs engaging the inner radial ends ofthe slots, outer end lips extending acros the outer open axial ends ofthe slots adjacent the radially inner ends of said slots, said outer endlips adapted to engage the axial ends of the springs, means on said stemoperatively associated with at least one of said end members for varyingthe spacing between said end members, whereby the force with which theabrasive members are thrust radially outwardly is varied, the lips onsaid first end member being small enough to leave the greater portion ofthe slots unobstructed, and said abrasive members extending axiallyoutwardly of said outer end lips on said first end member.

12. A grinding tool comprising a stem, a pair of axially spaced endmembers on said stem, at least one of said end members being movableaxially along said stem toward and away from the other end member toaccommodate a plurality of abrasive members of varying lengths, said endmembers being non-rotatable with respect to said stem, each end memberhaving a plurality of circumferentially spaced slots extending radiallytherein, the slots of said pair of end members being aligned, abrasivemembers, positioned in pairs of aligned slots, saidabrasive membersbeing of substantially uniform cross-section along their entire length,resilient means biasing said abrasive members radially outward from saidslots, means including elements on said abrasive members and elements onsaid end members-cooperating with each other to limit the radiallyoutward movement of said abrasive members with respect to said endmembers, elements extending from said abrasive members engageable withsaid end members for limiting axial movement of said abrasive memberswith respect to said end members, and said abrasive members extendingthrough the entire axial length of the slots in at least one of said endmembers and extending axially outward of said one end member, wherebysaid grinding tool is adapted to be applied to surfaces spaced axiallyoutward or said one end member when said tool is in its operativeenvironment.

13. A grinding tool comprising a stem, a pair of axially spaced endmembers on said stem, said end members being non-rotatable with respectto said stem, each end member having a plurality or circumferentiallyspaced slots extending radially therein, the slots of said pair of endmembers being aligned, abrasive members positioned in pairs ofalignedslots, leaf springs in engagement with each abrasive member forresiliently biasing said abrasive members radially outwardly, outer endlip extending across the outer open axial ends of the end member slotsadjacent the radially inner ends of said slots, the axial ends of saidleaf springs engaging said outer end lips, at least one of said endmembers being movable axially along said stem toward and away from theother end member to accommodate a plurality of abrasive member ofvarying lengths, means including elements on said abrasive members andelements on said end members cooperating with each other to limit theradially outward movement of said abrasive members with respect to saidend members, elements extending from said abrasive members engageablewith said end members for limiting axial movement of said abrasivemembers with respect to said end members, and said abrasive membersextending through the entire axial length of said slots in at least oneof said end members and outwardly of the lips on said one end member.

14. A grinding tool comprising a stem, a pair of axially spaced endmembers on said stem, said end members being non-rotatable with respectto said stem, each end member having a plurality of circumferentiallyspaced slots extending radially therein, the slots of said pair of endmember being aligned, abrasive members positioned in pairs of alignedslots, leaf springs in engagement with each abrasive member forresiliently biasing said abrasive members radially outwardly, outer endlips extending across the outer open axial ends of the end member slotsadjacent the radially inner ends of said slots, the axial ends of saidleaf springs engaging said outer end lips, at least one of said endmembers being movable axially along said stem toward and away from theother end member to accommodate a plurality of abrasive members ofvarying lengths, flanges on each end member extending toward the othermember lateral projections adjacent the radial inner portion of theabrasive members and losated between said end members, said projec tionsadapted toengage the radial inner surface of said flanges, whereby theradial outward movement of said abrasive members is limited, and saidabrasive members extending through the entire axial length of said slotsat least one of said end members and outwardly of the lips on said oneend member.

15. A grinding tool comprising a stem, 2, pair of axially spaced endmembers on said stem, said end member being non-rotatable with respectto said stem, each end member having a plurality of circumferentiallyspaced slots extending. radially therein, the slots of said pair of endmembers being aligned, abrasive members positioned in pairs of alignedslots, leaf springs in engagement with each abrasive member forresiliently biasing said abrasive members radially outwardly, outer endlips extending across the outer open axial ends of the end member slotsadjacent the radially inner ends of said slots, the axial ends of saidleaf springs engaging said outer end lips, at least one of said endmembers being movable axially along said stem toward and away from theother end member to accommodate a phirality of abrasive members'ofvarying lengths, lateral projections adjacent the radial inner portionof the abrasive members and located between said end members, saidlateral projections adapted to engage the axial innn'er surface of saidend members, whereby axial movement of said abrasive' members withrespect to said end members is limited, and said abrasive membersextending through the entire axial length of said slots in'at least oneofsaid end members and outwardly of the lip on said one end-member;

16. A grinding tool comprising astem, a pair of axially spaced endmembers mounted on said stem-each end member havinga plurality ofcircumferentially spaced slots extending radially therein, the slots ofsaid pair of end members being aligned, abrasive members positioned inpairs of aligned slots, resilient means biasing said 1'2. abrasivemembers radially outwardrof-said slots, means including elements on saidabrasive members and elements on said endmembers cooperating to limitthe radially outward movement of said abrasive members, at least one ofsaid end members being slidably. mounted on said stem and movableaxially along said stem toward and away from the other end member,resilient means applying forces to opposite sides of said one end memberin opposite axial directions, the reaction force of said resilient meansbeing transmitted to said stem, and means restricting rotation of saidend members relative to each other, said means comprising a portion ofsaid stem having a polygonal cross-section, and said end members havingapertures" of polygonal cross-section adapted to receive therethroughsaid polygonal portion of the stem.

THOMAS E. BROOKS.

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